1. Field of the Invention
This invention relates to a filter with a support structure for placing a filter inside of a street curb inlet catch basin below and down stream from the basin's curb inlet.
2. Description of the Prior Art
The inlet is typically in the curb of a street. Storm water flows off the street, down the gutter, through the curb inlet, then into the catch basin, and out the basin outlet. Before the ground water flows into a sewer line it needs to be filtered as free of pollutants as possible. These pollutants may include large debris such as sticks and leaves as well as soil.
In the past this filtration has been accomplished by placing a filter means in the mouth of the curb inlet. These devices often cause obstructions in the street and are subject to vandalism. For example Emery, U.S. Pat. No. 5,403,474 shows a containment of gravel that extends out into the street in front of the curb inlet. Other forms of curb inlet protection are designed to bar only large items from entering the catch basin. These do not filter out smaller pollutants or provide a means to retain these pollutants offsite of the street. For example, the approach described by Allen et al. U.S. Pat. No. 6,0154,489 shows a filter placed in the mouth of a curb inlet. This prevents large sized debris from entering the storm sewer system. The debris however, backs up into the street. In heavy flow conditions, storm water forces the filter open and allows the accumulated debris to enter the sewer system. There is no off-street containment of pollutants. McGowan U.S. Pat. No. 4,594,157 shows a clamp and screen that mounts inside the curb inlet. This provides no off-street containment of debris. The debris accumulates in the street upstream from the curb inlet. Other prior art refers to catch basin filters, which are not designed for curb inlet basins for example Logue Jr. U.S. Pat. No. 5,575,925.
The Drain Pack™ product brochure shows a filter basket installed below a curb inlet and essentially inside a curb inlet catch basin. This device appears to be designed to catch large pollutant items such as pop cans and sticks. The capacity of the basket is small and limited in size. The device does not have any means to convey the storm water from the inlet floor to the basket interior. Small pollutants will bypass the filter because the basket merely rests against the uneven cement basin wall without a seal. The basket is of a fixed length. There is no provision at the job site to expand the basket or series of baskets to a full width of the inlet opening. The device is attached to the exterior of the inlet mouth hanging from chains. This is subject to vandalism and expensive to install. The attachments appear to require drilling and alteration of the outsides of the inlet.
Other prior art is unnecessarily complex. For example Roy et al. U.S. Pat. No. 6,106,706 shows a pollutant filter apparatus that comprises an unnecessarily complex bypass means. The bypass is a moving part, which is subject to wear and to being jammed open with debris. During the winter, the movable part can freeze into position and cause the system to either not filter or backup storm water into the street. The hinged and spring-loaded bypass means is expensive to manufacture. The filter apparatus further comprises a permanently mounted structure inside the catch basin. This mounting structure is expensive to manufacture, install and remove. The catch basin is altered by screws, which require power tools to install. The apparatus cannot be adjusted on site to accommodate the various sizes of curb catch basins that are regularly encountered in the field.
Accordingly, what is needed is a filter system with a support structure comprising stationary parts. This system should be easy to install without the need for power tools, require no alteration of the catch basin, can be adjusted to fit catch basins of varying sizes and dimensions, and have none of the disadvantages of the foregoing prior art devices.